Triboelectric generating device and manufacturing method thereof

ABSTRACT

Disclosed are a triboelectric power generating device and a manufacturing method thereof, which does not require a physical space to generate friction motions unlike conventional pressured induced electric power generating devices, maximizes a surface area by the junction friction portion of a friction material composite that is inexpensive and easy to mass-produce, thereby improving the durability of a generating device, and effectively producing electricity. The triboelectric power generating device includes a triboelectric generation layer including a friction portion having a junction structure which is located at a central portion and made of two or more different polymers, a first electrode which is located to face one surface of the triboelectric generation layer, and a second electrode which is located to face the other surface of the triboelectric generation layer.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. application Ser. No. 16/764,903filed May 18, 2020, which is National Stage of International ApplicationNo. PCT/KR2018/013687 filed Nov. 12, 2018, claiming priority based onKorean Patent Application No. 10-2017-0156387 filed Nov. 22, 2017, thecontents of which are incorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to a triboelectric power generating deviceand more particularly, to a triboelectric power generating device and amanufacturing method thereof, which does not require a physical space togenerate friction motions unlike conventional pressured induced electricpower generating devices, maximizes a surface area by the junctionfriction portion of a friction material composite that is inexpensiveand easy to mass-produce, thereby improving the durability of agenerating device, and effectively producing electricity.

BACKGROUND ART

In the case of general pressured induced electric power generatingdevices, organic piezoelectric materials such as PVDF having excellentflexibility have a difficulty in producing a competitive product due toenvironmental hazards and high material cost. In addition, inorganicpiezoelectric materials having poor flexibility have a durabilityproblem that the material is ruptured by a continuous external pressure.In the case of triboelectric device, not only a physical space isrequired to generate frictional motion between friction materials, butalso a structure of the device is complicated and difficult to producein large scale, and since the degree of abrasion due to friction of amaterial is large, a problem of low reliability in durability occurs. Inaddition, existing triboelectric materials have a disadvantage that itis difficult to produce in large scale due to the difficulty in joiningan electrode and a friction material and the difference in the processmethod of applying the friction materials to the device. Therefore, itis required to develop a triboelectric generating device that iscompensated for such disadvantages.

Here, when describing the history of the development of the conventionaltriboelectric devices that have been conducted so far, in 2012, it wasconfirmed that different types of triboelectric materials werebilayered, and then electrodes face the outside, thereby producingelectricity through vertical and horizontal movement between thetriboelectric materials. In 2013, it was possible to produce electricityeven by intersecting different types of triboelectric materials, andindividual triboelectric devices were formed in a multiple layer(parallel structure) to improve power generation efficiency. In 2014, atriboelectric device having a three-dimensional structure greatlyimproved an amount of generated current, and it was confirmed thattriboelectric can be efficiently produced by rotating a disc electrodeand triboelectric material having the shape of a bicycle wheel about acentral axis, it showed that it is possible to efficiently produceelectricity by grating a thin-film triboelectric material by micron unitand overlapping with the electrode, and then moving horizontally, and itwas confirmed that a spring was attached to the grated triboelectricmaterial and the electrode to make it possible to move horizontallybetween the material and the electrode and to convert high efficiency(up to 85%) physical energy into electric energy through energyconservation through the spring.

In 2015, it showed that a structure was improved so that the frictionmaterials could move smoothly even with little energy applied byinserting a steel rod between the friction materials for the use of abearing, and nevertheless, triboelectric power generation efficiency wasnot lowered significantly. In addition, it was found that a hybridsystem can supply the amount of voltage or current more stably byconnecting an electromagnetic generator (AC) and a triboelectric element(AC) in series or in parallel. In addition, it was confirmed that powercan be produced simultaneously from light and kinetic energy byconnecting a solar cell (DC) and the triboelectric device (AC).Thereafter, researches are being conducted to improve the powergeneration efficiency through micro- or nano-unit patterning between thetriboelectric materials, and the efficiency has been further improved bychanging the material or the shape (vertical, horizontal, rotational,bent, etc.) of receiving the kinetic energy. The latest notable researchresult showed the possibility of use as a wind generator by fixing oneside of the triboelectric device to a substrate and leaving the otherside shaken in the wind.

DISCLOSURE Technical Problem

Unlike all the triboelectric devices introduced above, in atriboelectric device to be described in the present invention, power isgenerated by removing a physically unnecessary structure between thetriboelectric materials and using a phenomenon in which a contactbetween triboelectric material domains in nano units or maximum micronsunits is attached and detached by bending of the film. This is developedin terms of controlling the material surface shape of existing studies,and has also secured legitimacy by inheriting researches on utilizingvarious types of kinetic energy.

Therefore, it is an object of the present invention to provide atriboelectric generating device and a manufacturing method thereof,which does not require a physical space to generate a friction motionunlike conventional pressured induced electric power generating devices,and maximizes a surface area by the junction friction portion of afriction material composite that is inexpensive and easy tomass-produce, thereby improving the durability of a generating deviceand effectively producing electricity.

Technical Solution

In order to achieve the object, the present invention provides atriboelectric power generating device which includes a triboelectricgeneration layer 300 including a friction portion having a junctionstructure which is located at a central portion and made of two or moredifferent polymers, a first electrode 100 which is located to face onesurface of the triboelectric generation layer 300, and a secondelectrode 200 which is located to face the other surface of thetriboelectric generation layer 300.

In addition, the present invention provides a manufacturing method of atriboelectric power generating device, which includes the steps of a)dissolving and dispersing, or dissolving and dispersing and then mixing,or melting and mixing two or more polymers having different dielectricproperties in a solvent, respectively; b) masking a part of the surfaceof each of a first electrode and a second electrode having differentmaterials; c) forming a triboelectric generation layer on the electrodeby supplying a polymer solution which is mixed or unmixed in the step a)onto a unmasked exposed surface in one of the masked first and secondelectrodes; and d) laminating and then pressing the other electrode onwhich the triboelectric generation layer is not formed on thetriboelectric generation layer.

Advantageous Effects

The triboelectric power generating device and the manufacturing methodthereof according to the present invention does not require a physicalspace to generate friction motions unlike conventional pressured inducedelectric power generating devices, and maximizes a surface area by thejunction friction portion of a friction material composite that isinexpensive and easy to mass-produce, thereby improving the durabilityof a generating device, and effectively producing electricity.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side cross-sectional schematic view of a triboelectric powergenerating device according to an example of the present invention.

FIG. 2A and FIG. 2B are schematic views of an electrode masked accordingto the present invention.

FIG. 3 is a side cross-sectional schematic view of a triboelectric powergenerating device according to another example of the present invention.

FIGS. 4 and 5 are side cross-sectional schematic views of atriboelectric power generating device according to yet another exampleof the present invention.

FIG. 6 is a graph of measuring a voltage and a current according to animpact applied to a triboelectric power generating device according toan example of the present invention.

FIGS. 7 to 9 are graphs of measuring a voltage and a current accordingto an impact applied to a triboelectric power generating deviceaccording to the comparative examples of the present invention.

FIGS. 10 to 12 are graphs of measuring a voltage and a current accordingto an impact applied to a triboelectric power generating deviceaccording to other examples of the present invention.

BEST MODE

Hereinafter, the present invention will be described in detail withreference to the accompanying drawings.

FIG. 1 is a side cross-sectional schematic view of a triboelectric powergenerating device according to an exemplary embodiment of the presentinvention. As illustrated in FIG. 1 , a triboelectric power generatingdevice according to the present invention includes a triboelectricgeneration layer 300 including a friction portion having a junctionstructure which is located at a central portion and made of two or moredifferent polymers, a first electrode 100 which is located to face onesurface of the triboelectric generation layer 300, and a secondelectrode 200 which is located to face the other surface of thetriboelectric generation layer 300.

The triboelectric power generating device according to the presentinvention is a device capable of converting all physical kinetic energyapplied from the outside into electrical energy, can be utilized forwind power generation, tidal power generation, wave power generation andthe like, and may be configured by a module in which a plurality ofdevices are repeatedly arranged and a generator in which a plurality ofthe modules are repeatedly arranged in order to implement each powergeneration method. In addition, the triboelectric power generatingdevice according to the present invention can detect a physical motion,texture, hardness, or applied force and thus can be utilized even as asensor.

The triboelectric generation layer 300 is a triboelectric compositematerial in the form of a film including a friction portion forgenerating electricity, and the friction portion is formed of randomjunction portions in nanometers (nm) to micrometer (μm) units. Thejunction portion may have a bulk-heterojunction structure in which twoor more different materials are not uniformly contacted, or may have amulti junction structure, for example, a structure similar to an activelayer of a bulk-heterojunction organic photovoltaics (see website).Meanwhile, the multi junction structure is basically similar to thebulk-heterojunction structure, but may be a structure in which two ormore materials are in contact with each other in a more regular shape(see website). Thus, despite the extremely short travel distances ofeach polarized triboelectric material, a surface area is maximized,thereby improving the reliability of the material durability andefficiently producing electricity.

Meanwhile, the triboelectric generation layer 300 has a thickness of 1nm to 10,000 μm, preferably 100 nm to 5,000 μm, and more preferably 1 to1,000 μm. When the thickness of the triboelectric generation layer 300exceeds 10,000 μm, an electric field formed by the separation of chargesgenerated at the junction portion does not affect a collector electrode,which may cause a problem that voltage and current cannot be generated.When the thickness of the triboelectric generation layer 300 is lessthan 1 nm, a distance between the collector electrodes is too close, andthus a short phenomenon in devices may occur due to a tunnelingphenomenon.

The triboelectric generation layer (or the friction portion) is made oftwo or more different polymers having different dielectric properties,preferably two different polymers. The polymers may be materials thatare inexpensive to manufacture and easy to mass-produce, that is, forexample, polyamide, polyvinyl alcohol (PVA), polymethylmethacrylate(PMMA), polyester, polyurethane, polyvinyl butyral (PVB),polyacrylonitrile, natural rubber, polystyrene (PS), polyvinylidenechloride, polyethylene (PE), polypropylene (PP), polyimide,polyvinylchloride (PVC), and polydimethylsiloxane (PDMS), and preferablya mixture of PVC and PMMA, a mixture of PVC and PVA, a mixture of PVCand PVB, a mixture of PP and PMMA, and a mixture of PE and PMMA. Whenthe polymers are used in two kinds of mixture (i.e., when thetriboelectric generation layer includes two different polymers), themixing (including) ratio of the polymers is a weight ratio of 0.1:99.9to 99.9:0.1. Despite including one of the two polymers in a smallamount, the effect according to the present invention occurs, and themixing ratio of the polymers may be preferably a weight ratio of 20:80to 80:20, more preferably a weight ratio of 40:60 to 60:40. In addition,each of the polymers preferably has a weight average molecular weight(Mw) of 10,000 to 5,000,000.

As such, when the friction portion is composed of polymers havingdifferent dielectric properties, a binding between a backbone betweenpolymers having different dielectric properties and a functional groupis broken to form radicals, which means that a charge transfer betweenthe two materials may occur due to a material transfer formed byelectrons or radicals. In addition, when ionic monomolecules are alreadypresent in the polymer or are formed due to friction, the ionicmonomolecules may also migrate between heterogeneous polymers, which maycause a charge transfer. For this reason, charges between the twomaterials are separated to generate triboelectricity.

Meanwhile, in order to more increase the mass-productivity of thepolymer materials, general-purpose solvents, such as acetone,tetrahydrofuran (THF), toluene, dichloromethane, chloroform, toluene,hexane, cyclohexane, dimethyl sulfoxide, NMP, water, and the like, maybe used. That is, a composite material such as a composite film orcomposite particles may be formed by dissolving and then mixing thedifferent polymers in such a solvent, melting and mixing the polymers inthe solvent, or water-borne or solvent-borne dispersing and then mixingthe different polymers in aqueous and non-aqueous solvents (that is,emulsion polymerization).

Accordingly, the triboelectric power generating device according to thepresent invention has a simple structure in which the triboelectricgeneration layer (or the triboelectric material composite) 300, which iseasy to mass-produce, is located (inserted) between both electrodes (thefirst electrode 100 and the second electrode 200) and then a coatinglayer 400 for water-proof/moisture-proof and a coating layer 500 forsupporting are coated. Thus, since the triboelectric generating devicehas a very simple structure as compared to existing triboelectricdevices, which has a structure similar to existing commerciallyavailable pressured induced electric power generating devices,mass-productivity and reliability are high.

Next, the first electrode 100 and the second electrode 200 are made ofconductive materials that allow electricity to flow by the chargingphenomenon, and any conductive material that satisfies this may beapplied without particular limitation. Examples of such conductivematerials may include copper, aluminum, gold, silver, carbon felt,carbon paper, a composite added with carbon nanotubes (CNT), and thelike, and the electrode is not particularly limited in its form such asporous foam in addition to the usual film form.

However, the first electrode 100 and the second electrode 200 may beformed of different materials, respectively. In addition, the firstelectrode 100 and the second electrode 200 have thicknesses of 20 nm to5 mm, preferably 50 nm to 1 mm, and more preferably 100 nm to 100 um.When the thickness of the first electrode 100 and the second electrode200 exceeds 5 mm, the flexibility corresponding to the wind of thedevice may be lowered, and when the thickness thereof is less than 20nm, the performance of the device may be deteriorated due to an increasein resistance.

Meanwhile, the first electrode 100 and the second electrode 200 may beconfigured such that one end of each electrode protrudes from thetriboelectric generation layer 300 in order to couple (ground) the wire(see FIG. 2A and FIG. 2B). In addition, in the present invention, thefirst electrode 100 and the second electrode 200 prevent a shortphenomenon between both electrodes. Further, in order to identicallymaintain the area of the triboelectric generation layer 300 for eachdevice, other remaining external exposed surface except for a partfacing the triboelectric generation layer 300 may be masked by a tapecoated with an adhesive component or an insulating material such as PPor PE. FIG. 2A and FIG. 2B are schematic views of an electrode maskedaccording to the present invention, wherein the masking treatment of theelectrode may be performed on both sides (a and b of FIG. 2A) asillustrated in FIG. 2A, may also be performed only on one side asillustrated in FIG. 2B, and may vary depending on the performance andthe like of a target electrode. In addition, the content of basic rolesof electrode not described above may comply with the content ofelectrode used in the conventional triboelectric device.

FIG. 3 is a side cross-sectional schematic view of a triboelectric powergenerating device according to another example of the present invention.On the other hand, the triboelectric power generating device, asillustrated in FIG. 3 , may further include at least a pair of firstcoating layers 400 which are located on the outer peripheral surface ofeach of the first and second electrodes 100, 200 to prevent water,moisture, and oxygen, and the like, if necessary. In addition, thetriboelectric generating device may further include at least a pair ofsecond coating layers 500 which are located on the outer peripheralsurface of each of the first coating layers 400 to be supported.

Specifically, the first coating layer 400 is a layer for improvingwater-proof, moisture-proof, oxygen blocking, weather resistance,durability, and the like of the triboelectric power generating deviceaccording to the present invention and blocking the inside of the devicefrom the outside. Examples of the material thereof may include epoxy,polyester, polyurethane, a mixture of paraffin wax and polyolefin,polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE),polystyrene (PS), polyvinyl chloride (PVC), polyethylene naphthalate(PEN), polyamide (PA), polyvinyl alcohol (PVAL), ethylene vinyl alcohol(EVOH), polyvinylidene chloride (PVDC), and mixtures thereof, and may beused without particular limitation so long as the material has at leastone property of water-proof, moisture-proof, oxygen blocking, weatherresistance, and durability.

In addition, the second coating layer 500 basically has a function ofsupporting the triboelectric generating device, and may also have thefunction of the first coating layer 400, and more precisely, is a layerfor applying elasticity to the device. Example of the material of thesecond coating layer 500 may include polyimide, polyether ether ketone,mixtures thereof, and mixtures of at least one thereof and compoundsconstituting the first coating layer 400, and any materials may be usedwithout particular limitation so long as the material enables thetriboelectric power generating device to have a supporting function suchas flexibility and durableness.

The thickness of the first coating layer 400 is 100 nm to 10 mm,preferably 1 um to 1 mm, and more preferably 10 to 100 um. When thethickness of the first coating layer 400 is out of the above range,there may be a problem that the flexibility of the device is reduced ora function such as water-proof/moisture-proof is not sufficientlyperformed. Meanwhile, both ends of the first coating layer 400 may beconfigured to protrude from both ends of the first and second electrodes100, 200 as illustrated in FIG. 3 in order to protect the entire deviceincluding the collector electrode from water, moisture, and oxygen.

In addition, the thickness of the second coating layer 500 is 1 um to 10mm, preferably 5 um to 5 mm, and more preferably 10 um to 1 mm. When thethickness of the second coating layer 500 is out of the above range,there may be a problem that the flexibility of the device is reduced orthe function of supporting the device is not be sufficiently performed.Meanwhile, in FIG. 3 , the lengths of the first coating layer 400 andthe second coating layer 500 are the same, but this is only an example,and any one end or both ends of the second coating layer 500 may also beconfigured to protrude from the first coating layer 400. With such aprotruding configuration, the coating layer is completely coated(wrapped) once more by an outer support layer, thereby improving ablocking effect from the outside.

FIGS. 4 and 5 are side cross-sectional schematic views of atriboelectric power generating device according to yet another exemplaryembodiment of the present invention. Meanwhile, the triboelectric powergenerating device according to the present invention, if necessary, asillustrated in FIG. 4 , may further include a first interface layer 600and a second interface layer 700, including a material selected from thegroup consisting of polyamide, polyvinyl alcohol (PVA),polymethylmethacrylate (PMMA), polyester, polyurethane, polyvinylbutyral (PVB), polyacrylonitrile, natural rubber, polystyrene (PS),polyvinylidene chloride, polyethylene (PE), polypropylene (PP),polyimide, polyvinylchloride (PVC), and polydimethylsiloxane (PDMS),between the triboelectric generation layer 300 and the first electrode100, and between the triboelectric generation layer 300 and the secondelectrode 200, respectively. In addition, the triboelectric powergenerating device according to the present invention includes the firstinterface layer 600 and the second interface layer 700 formed of aplurality of layers which may be cross-laminated with the triboelectricgeneration layer 300 as necessary to improve the performance of thedevice as illustrated in FIG. 5 , and the order thereof is not limitedto FIG. 5 , and may be formed in various combinations in considerationof device performance.

The first interface layer 600 and the second interface layer 700 are tofurther improve an interaction with the triboelectric generation layer300 and a generation degree of electricity by preventing charges fromflowing reversely from the triboelectric generation layer 300. The firstinterface layer 600 and the second interface layer 700 have differenttriboelectric polarities, and for example, when the first interfacelayer 600 is PMMA, the second interface layer 700 may be PVC.Specifically, when any one of the first interface layer 600 and thesecond interface layer 700 is selected from the group consisting ofPMMA, polyamide, polyvinyl alcohol, polybutyral, and polystyrene, theother interface layer may be selected from the group consisting of PVC,PDMS, polypropylene, polyethylene, and polyvinylidine chloride.

In addition, the thickness of the first interface layer 600 and thesecond interface layer 700 is 1 nm to 1 mm, preferably 50 nm to 500 um,and more preferably 100 nm to 100 um. When the thicknesses of the firstinterface layer 600 and the second interface layer 700 are out of theabove range, there may be a problem that the flexibility of the deviceis reduced, the generation performance of the device is lowered, or afunction of blocking charges that move reversely from the triboelectricgeneration layer 300 is not properly performed.

Meanwhile, the widths (width×length, based on an appearance viewed fromthe top) of the triboelectric generation layer 300, the first electrode100, the second electrode 200, the first coating layer 400, the secondcoating layer 500, the first interface layer 600, and the secondinterface layer 700 described so far are not particularly limited, andmay vary depending on the size and characteristics of a targettriboelectric power generating device.

Next, a manufacturing method of a triboelectric power generating deviceaccording to the present invention will be described with reference toFIGS. 1 and 3 . The manufacturing method of the triboelectric powergenerating device includes the steps of a) dissolving and dispersing, ordissolving and dispersing and then mixing, or melting and mixing two ormore polymers having different dielectric properties in a solvent,respectively; b) masking a part of the surface of each of a firstelectrode and a second electrode having different materials; c)supplying a polymer solution which is mixed or unmixed in step a) ontothe unmasked exposed surface of any one of the masked first and secondelectrodes (the second electrode 200 in the drawing), and then drying orcuring the polymer solution to form a triboelectric generation layer (ora polymer composite film) 300 on the electrode; and d) laminating andthen pressing the other electrode (the first electrode 100 in thedrawing), on which the triboelectric generation layer 300 is not formed,on the top of the triboelectric generation layer 300.

Meanwhile, after at least one of steps c) and d) is performed, a processof annealing the triboelectric generation layer 300 may be performed,and the manufacturing method of the triboelectric power generatingdevice further includes the steps of e) forming a first coating layer400 on the outer peripheral surface of each of the first electrode 100and the second electrode 200, and f) forming a second coating layer 500on the outer peripheral surface of each of the first coating layers 400,if necessary.

According to the present invention, in order to manufacture thetriboelectric power generating device, first, it needs to dissolve anddisperse, dissolve, disperse, and then mix, or melt and mix two or morepolymers having different dielectric properties in an solvent,respectively (in the case of emulsion polymerization, mixing awater-borne solution and a solvent-borne solution, step a). The polymer(material) constitutes a friction portion for generating electricity inthe triboelectric power generating device, and the detailed descriptionthereof complies with the contents of the polymers described in thetriboelectric power generating device. On the other hand, when thepolymer is not mixed after being dissolved and dispersed in eachsolvent, a laminated-type triboelectric power generating device may bemanufactured by sequentially supplying each polymer solution on anelectrode.

Dissolving/dispersing the polymer in the solvent is a unique process ofthe present invention for further improving the mass-productivity of thepolymer. Examples of the solvent that can be used may include organicsolvents, such as linear and cyclic alkane-based compounds,aromatic-based compounds, ketone-based compounds, linear and cyclicether-based compounds, amine-based compounds, sulfide-based compounds,and halogen-based compounds. More specifically, examples of generalsolvents may include hexane, cyclohexane, toluene, acetone, diethylether, tetrahydrofuran (THF), N-methyl-2-pyrrolidone, dimethylsulfoxide, dichloromethane, and chloroform.

The concentration at which the polymer is dissolved in the solvent is0.1 to 10,000 g/kg, preferably 1 to 5,000 g/kg, and more preferably 10to 1,000 g/kg. When the concentration at which the polymer is dissolvedin the solvent is out of the above range, an effect obtained bydissolving the polymer in the solvent may be insignificant or the mixingprocess may be difficult. In addition, the temperature at which thepolymer is dissolved in the solvent is 0° C. to 70° C., preferably 10°C. to 50° C., and more preferably 25° C. to 40° C. When the temperatureat which the polymer is dissolved in the solvent is out of the aboverange, there may be a problem that the polymer is insoluble ordecomposed, or increases the risk of explosion.

At this time, a mixing ratio of each polymer solution may be a weightratio of 0.1:99.9 to 99.9:0.1, preferably a weight ratio of 20:80 to80:20, and more preferably a weight ratio of 40:60 to 60:40. Meanwhile,when performing step a) of mixing the different polymer solutions, inorder to reinforce the flexibility and impact strength of each polymermaterial, additives such as plasticizers and impact modifiers may beadditionally added, if necessary.

Next, after preparing the electrodes (the first electrode and the secondelectrode) having different materials, a part of each surface is masked(step b). The first electrode and the second electrode should be made ofdifferent materials to enable the generation of triboelectricity. Thereason for masking a part of the surface of the first and secondelectrodes with a tape is to prevent a short phenomenon between bothelectrodes and to keep an area of the triboelectric generation layer thesame for each device, so that a part to which the polymer mixed solutionis not to be applied (or supplied) is defined as a masking applicationportion. In addition, the detailed description of the electrodes and themasking complies with the contents of the electrodes and maskingdescribed in the triboelectric power generating device.

After the surface of each electrode is masked, by supplying a polymersolution which is mixed or unmixed in step a) on a unmasked exposedsurface in any one of the first and second electrodes (the secondelectrode 200 in the drawing), and then drying or curing the polymersolution to form a triboelectric generation layer (or a polymercomposite film 300) on an electrode (step c). As the method of supplyingthe polymer mixed solution on the electrode, there are drop casting,screen printing, spin coating, rotogravure printing, spray coating,inkjet printing, and the like. In addition, the triboelectric generationlayer 300 has a thickness of 1 nm to 10,000 μm, preferably 100 nm to5,000 μm, and more preferably 1 to 1,000 μm. When the thickness of thetriboelectric generation layer 300 exceeds 10,000 μm, an electric fieldgenerated by the separation of charges generated at a junction portiondoes not affect a collector electrode, which may cause a problem thatvoltage and current cannot be generated. When the thickness thereof isless than 1 nm, a distance between the collector electrodes is tooclose, which may cause a short phenomenon in devices due to a tunnelingphenomenon.

Meanwhile, the manufacturing method of the triboelectric powergenerating device further includes the step of re-supplying the polymermixed solution used in step c) one or more times, preferably 1 to 100times, and more preferably 5 to 20 times onto the surface of the polymercomposite film (the triboelectric generation layer) formed in step c)and then drying the solution, if necessary. As this is a process foradjusting the thickness of the polymer composite film, as theconcentration of the polymer in step a) is lowered, the number ofre-supplying times may be increased. Therefore, when the concentrationof the polymer is high, the re-supplying process of such a polymer mixedsolution may not be performed.

In addition, it is described in the present specification that thepolymer solution and the mixed solution are first prepared, and then thesurface of the electrode is masked, but this is only for convenience ofdescription and the order thereof may be changed or proceedsimultaneously.

When the triboelectric generation layer is formed on the electrode asdescribed above, the other electrode (the first electrode 100 in thedrawing) in which the triboelectric generation layer 300 is not formedis laminated and then pressed on the annealed triboelectric generationlayer 300. The pressing may be performed under a temperature of 40° C.to 250° C. and a pressure of 1 gF to 100 kgF by a general pressingmethod such as a roll-press method and a hot-press method.

On the other hand, after at least one of steps c) and d) is performed, aprocess of annealing the triboelectric generation layer 300 isperformed. The annealing process is a process in which the triboelectricgeneration layer 300 is made at a predetermined temperature, maintainedat the corresponding temperature for a predetermined time, and thencooled to room temperature, and is used for optimizing the powergeneration efficiency according to the control of the total junctionarea by controlling the aggregation degree of polymers in thetriboelectric generation layer 300. The temperature, the required time,and the number of times of the annealing process may be arbitrarilychanged in consideration of physical properties of the target powergenerating device, but the annealing process may be performed 1 to 24times, preferably 1 to 10 times at a temperature of 30° C. to 250° C.,preferably 50° C. to 150° C. for 1 to 3,600 seconds, preferably 10 to180 seconds.

Meanwhile, when the annealing process is performed, as illustrated inFIG. 4 , the interface layers (the first interface layer 600 and thesecond interface layer 700 in FIG. 4 ) may be formed between thetriboelectric generation layer 300 and the first electrode 100, andbetween the triboelectric generation layer 300 and the second electrode200 (alternatively, on both sides of the triboelectric generation layer300), respectively. This is a phenomenon in which the polymer of thetriboelectric generation layer 300 leaks up and down by heating duringthe annealing process, and is caused by a difference in density. Thefirst interface layer 600 and the second interface layer 700 may beinduced to be formed with polymers having opposite triboelectricpolarities to each other.

Meanwhile, in addition to the method formed by the annealing process,the interface layer may be intentionally formed at a time before formingthe triboelectric generation layer (or the polymer composite film) 300on the electrode. Accordingly, as illustrated in FIG. 5 , the firstinterface layer 600 and the second interface layer 700 may be formed ofa plurality of layers to be cross-laminated with the triboelectricgeneration layer 300, and the order thereof is not limited to FIG. 5 andmay be formed in various combinations in consideration of deviceperformance. Here, when the triboelectric device is configured asillustrated in FIG. 5 , the performance of the device may be furtherimproved.

Meanwhile, after forming the first coating layer 400 in step e) or evenafter forming the second coating layer 500 in step f), the annealingprocess may be further performed, if necessary. In addition, thedescription of the material, the thickness, and the like of the firstcoating layer 400 and the second coating layer 500 complies with thecontents described in the triboelectric power generating device.

Hereinafter, the present invention will be described in more detail withreference to specific examples. The following examples are illustrativeof the present invention and the present invention is not limited to thefollowing examples.

[Example 1] Preparation of Triboelectric Power Generating Device

First, PMMA was dissolved in tetrahydrofuran (THF) at room temperatureat a concentration of 0.1 g/mL, and PVC was also dissolved in THF atroom temperature at the same concentration of 0.1 g/mL, and then thePMMA solution and the PVC solution were mixed at a weight ratio of 1:1to prepare a polymer mixed solution.

Next, after bonding an aluminum electrode having a size of 4.3 cm×9cm×10 μm on the surface of a PET coated paper coated with an acrylicadhesive and washing the surface of the electrode with acetone, in theform as illustrated in FIG. 2 , two electrode films were prepared, inwhich the remaining portion except for an area (exposed electrode) of4.3 cm×8 cm was masked by a Scotch tape.

Subsequently, on the surface of one exposed (unmasked) electrode film, aPMMA-PVC polymer mixed solution was bar-coated and dried to form atriboelectric generation layer, and then the PMMA-PVC polymer mixedsolution was additionally bar-coated 5 times on the upper side (surface)of the triboelectric generation layer and dried.

Thereafter, one masked electrode film was laminated on the electrodesurface coated with the PMMA-PVC polymer mixed solution, and then atriboelectric generation layer was annealed at 70° C. to 90° C. forabout 5 seconds by using a laminator (Kolami-320S, Kolami, in Korea) andpressed at a pressure of about 1 kgF to prepare a triboelectric powergenerating device.

[Example 2] Preparation of Laminated-Type Triboelectric Power GeneratingDevice

A triboelectric power generating device was prepared in the same manneras in Example 1, except that the PVC and PMMA layers were sequentiallycoated one time and laminated without mixing the PVC and PMMA solutions.

[Example 3] Preparation of Laminated-Type Triboelectric Power GeneratingDevice

A triboelectric power generating device was prepared in the same manneras in Example 2, except that the PVC and PMMA layers were alternatelycoated 3 times and laminated.

[Example 4] Preparation of Laminated-Type Triboelectric Power GeneratingDevice

A triboelectric power generating device was prepared in the same manneras in Example 2, except that the PVC and PMMA layers were alternatelycoated 5 times and laminated.

[Comparative Example 1] Preparation of Triboelectric Power GeneratingDevice

A triboelectric power generating device was prepared in the same manneras in Example 1, except that drop casting, drying, and annealingprocesses were excluded by not using the polymer mixed solution.

[Comparative Example 2] Preparation of Triboelectric Power GeneratingDevice

A triboelectric power generating device was prepared in the same manneras in Example 1, except that a PMMA polymer solution was used byexcluding a PVC solution instead of a PMMA-PVC polymer mixed solution(that is, the triboelectric generation layer was configured by only aPMMA polymer).

[Comparative Example 3] Preparation of Triboelectric Power GeneratingDevice

A triboelectric power generating device was prepared in the same manneras in Example 1, except that a PVC polymer solution is used by excludingthe PMMA solution instead of a PMMA-PVC polymer mixed solution (that is,the triboelectric generation layer was configured by only a PVC polymer)

[Example 1 and Comparative Examples 1 to 3] Evaluation of TriboelectricGeneration Amounts

After a multimeter (UT61E, UNI-T Co., Ltd., China) was connected withboth electrodes of the triboelectric power generating devices preparedin Example 1 and Comparative Examples 1 to 3 with wires, changes involtage depending on an impact applied to the devices were measured.That is, the device was bent up and down three times per second (3 Hz)for 20 seconds after a first pause of 10 seconds, and subsequently,after a pause of 10 to 20 seconds, the remaining process except for thefirst pause was additionally repeated 2 times.

FIG. 6 is a graph of measuring a voltage and a current according to animpact applied to a triboelectric power generating device according toan example of the present invention and FIGS. 7 to 9 are graphs ofmeasuring a voltage and a current according to an impact applied to atriboelectric power generating device according to the comparativeexamples of the present invention. Here, FIG. 6 corresponds to Example 1and FIGS. 7 to 9 correspond to Comparative Examples 1 to 3,respectively. First, in the case of the triboelectric power generatingdevice prepared in Example 1 (using the polymer composite film), asillustrated in FIG. 6 , it could be confirmed that electricity wasimmediately generated depending on an impact/change applied to thedevice.

On the other hand, in the case of the device prepared in ComparativeExample 1 (without using the polymer composite film), as illustrated inFIG. 7 , it can be seen that triboelectricity was not generated at all.In the case of the device prepared in Comparative Example 2 (using onlythe PMMA polymer), as illustrated in FIG. 8 , it can be confirmed thatelectricity was generated, but it is significantly less than Example 1.In the case of the device prepared in Comparative Example 3 (using onlythe PVC polymer), as illustrated in FIG. 9 , it can be confirmed thatonly a very small amount of electricity is generated.

[Examples 2 to 4] Evaluation of Triboelectric Generation Amounts

After a multimeter (UT61E, UNI-T Co., Ltd., China) was connected withboth electrodes of the laminated-type triboelectric power generatingdevices prepared in Examples 2 to 4 with wires, voltage changesdepending on an impact applied to the devices are measured. That is, thedevice was bent up and down three times per second for 20 seconds aftera first pause of 10 seconds, and subsequently, after a pause of 10 to 20seconds, the remaining process except for the first pause isadditionally repeated 2 times.

FIGS. 10 to 12 are graphs of measuring a voltage and a current accordingto an impact applied to a triboelectric power generating deviceaccording to other examples of the present invention, and FIGS. 10 to 12correspond to Examples 2 to 4, respectively. In the laminated-typetriboelectric power generating devices prepared in Examples 2 to 4, asin Example 1 for the triboelectric power generating device which is nota laminated type, it can be confirmed that the electricity isimmediately generated depending on an impact/change applied to thedevice (see FIGS. 10 to 12 ). In addition, it can be confirmed that asthe number of laminated layers increases, the voltage and overallcurrent amount of electricity generated increases.

1. A manufacturing method of a triboelectric power generating devicecomprising: a) dissolving and dispersing, or dissolving and dispersingand then mixing, or melting and mixing two or more polymers havingdifferent dielectric properties in a solvent, respectively; b) masking apart of the surface of each of a first electrode and a second electrodehaving different materials; c) forming a triboelectric generation layeron the electrode by supplying a polymer solution which is mixed orunmixed in step a) onto a non-masked exposed surface in one of themasked first and second electrodes, and then drying or curing thesolution; and d) laminating and then pressing the other electrode whichis not formed with the triboelectric generation layer on thetriboelectric generation layer.
 2. The manufacturing method of thetriboelectric power generating device of claim 1, wherein after at leastone of steps c) and d) is performed, a process of annealing thetriboelectric generation layer is performed.
 3. The manufacturing methodof the triboelectric power generating device of claim 1, wherein thesolvent is selected from the group consisting of linear and cyclicalkane-based compounds, aromatic-based compounds, ketone-basedcompounds, linear and cyclic ether-based compounds, amine compounds,sulfide-based compounds, and halogen-based compounds.
 4. Themanufacturing method of the triboelectric power generating device ofclaim 1, wherein a mixing ratio of each polymer solution is a weightratio of 0.1:99.9 to 99.9:0.1.
 5. The manufacturing method of thetriboelectric power generating device of claim 1, further comprising: e)forming a first coating layer on the outer peripheral surface of each ofthe first electrode and the second electrode; and f) forming a secondcoating layer on the outer peripheral surface of each of the firstcoating layers.
 6. The manufacturing method of the triboelectric powergenerating device of claim 5, wherein the first coating layer isselected from the group consisting of epoxy, polyester, polyurethane, amixture of paraffin wax and polyolefin, polyethylene terephthalate,polypropylene, polyethylene, polystyrene, polyvinyl chloride,polyethylene naphthalate, polyamide, polyvinyl alcohol, ethylene vinylalcohol, polyvinylidene chloride, and mixtures thereof, and the secondcoating layer is selected from the group consisting of polyimide,polyether ether ketone, mixtures thereof, and mixtures of at least onethereof and compounds constituting the first coating layer.
 7. Themanufacturing method of the triboelectric power generating device ofclaim 1, further comprising: re-supplying the polymer mixed solutionused in step c) one time or more onto the surface of the triboelectricgeneration layer formed in step c) and then drying the solution.
 8. Themanufacturing method of the triboelectric power generating device ofclaim 1, wherein a laminated-type triboelectric power generating deviceis prepared by dissolving and dispersing the polymer in each solvent andthen sequentially supplying each polymer solution onto the electrodewithout mixing.